Technical note: Water table mapping accounting for river–aquifer connectivity and human pressure

Abstract

Abstract. A water table mapping method that accounts for surface-water–groundwater (SW-GW) connectivity and human pressure, such as pumping and underground structures occurrence, has been elaborated and tested in the heavily urbanized Parisian area. The method developed here consists of two steps. First, hard data (hydraulic head) and soft data (dry wells) are used as conditioning points for the estimation of the SW-GW connection status. A disconnection criteria of 0.75 m is adjusted on observed unsaturated zone depth (UZD). It is a default value in areas where such data are missing. The second step consists of the final mapping of the water table. Given the knowledge of the disconnection criteria, the final map is achieved with an ordinary kriging of the UZD that integrates the surface water elevation without unsaturated zone where it is relevant. The methodology is demonstrated on two datasets of UZD observations that were collected under low- and high-flow conditions.

Catchment‐Scale Architecture of the Deep Critical Zone Revealed by Seismic Imaging

“…Our understanding of the processes controlling the functioning and evolution of the CZ remains obscured by the difficulty of accessing information at depth. The CZ architecture (i.e., the depth of the water table and the main weathering interfaces) is often characterized with boreholes and piezometric wells, but data remain limited by costs, field access, spatial coverage and the destructive nature of such measurements (Holbrook et al, 2019;Hubbard & Linde, 2011;Maillot et al, 2019). Minimally invasive surface-based geophysical methods can be used to fill spatial gaps between wells by producing higher lateral resolution and lower cost data (Hubbard & Linde, 2011;Parsekian et al, 2015).…”